Hand-operated dental tool.



PATEN-TBD AUG.. 15, 1905u No. 797l06.

(L 13,. GRAY. HAND PERATED DENTAL TUL.l MPLIOATIW IIL@ JULY 1s, 1904.

' Lig-N Y /r/vEss/Ss f @MLM ZM ATTORNEY.

CHARLES P. (Ji-RAY, OF OlllClNNATl, OHlO.

HAND-@PERATED DENTAL TOOL.

Specification of' Letters Patent.

Patented Aug. 15, 1905.,

Application led July 13, 1904. Serial No. 216,345.

To all whom, it nt/ny cm1/067171,:

Be it known that l, CHARLES P. GRAY, a citizen of the United States, residingl at Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in lland Operated Dental Tools, of which the following is a specification.

My invention relates to improvements in tools for holding and operating breaches, drills, and the like by hand.

The object of my invention is to provide a tool of this character to enable the dental operator to conveniently and safely drill or operate on any of the roots of the teeth of the patient, and especially to remove the nerves from the roots of the rear teeth and ream the nerve-canals of same without inserting the fingers into the mouth and by operating the tool with the fingers on the outside of the mouth.

My invention consists in a dental tool comprising clampingjaws, beveled gear-retaining sleeve, holding-screw, housing, handle, shaft, and rotator.

My invention also consists in the parts and combination and arrangement of the several parts and in the details of construction as herein set forth and claimed.

ln the drawings, Figure 1 is a side view of my tool and operating instrument in place. Fig. 2 is a plan view of the same. Fig. 3 is a partial longitudinal vertical section of Fig. 1. Fig. L is an enlarged sectional view of the operating end of the tool, the operating instrumen t, shaft, and part of the holding-screw being shown in side elevation. Fig. 5 is an enlarged detail plan View of the operating end with the holding-screw removed. Fig. 6 is an enlarged side elevation of the beveled gear-retaining sleeve, holding-screw, and clamping-jaws. Fig. 7 is a detail side View of the clamping-jaws removed, the iiat face of each being toward the other and part of one of said jaws being broken away to show the central longitudinal groove on its flat face.

The preferred construction of my improved dental handpiece is substantially as follows: The handle, made up of the divided tubular portion 11 and the end portion 13 mounted on one of the divisions of the tubular portion 11, supports the slotted sleeve 12. Within the tubular handle is mounted a shaft 14,

An open holadapted to be rotated therein.

low head 1 is mounted upon the end of the handle opposite from that upon which the end portion 13 is mounted. Located within the hollow head 1 is the tool-holding chuck, made up of the chuck-easing 5, jaws 7, and holding screw 9 engaging' the jaws. The chuck-casing 5 is provided with gear-teeth, as is also the shaft lil.. These gears are intermeshed so that when the shaft is rotated its motion is transmitted to the chuck and to any tool, as 20, which may be held by the jaws 7. Preferably the hollow head 1 is formed at an angle to the handle 11 and the chuck-casing geared to the shaft 11.1. at an angle. Mounted upon the shaft 14 within the slot of the slotted sleeve 12 is the rotator 16 and held rig-- idly to the shaft by means of a screw i7 tal.:- ing into the circumferential channel 1H and bearing against the bottom thereof, end wise movement of the shaft being prevented by the said walls of said channel bearing against the screw 17 and by the end portions of the rotator 16 bearing against the end portions of the slot in the slotted sleeve .12. Suitable oilholes are provided through which to lubricate the bearings. The end 13 of the handle may be formed hollow to serve as a receptacle, or, if preferred, it may be formed slotted. Y The rotator 16 and other parts to be turned, such as the end portion 13 and the handle 11, are preferably knul-led to render them more easy to operate.

My invention is designed especially for the use of dentists in the treatment of the roots of teeth, and especially those diiiieult of ac- .cess for the removal of nerves, drilling or reaming the nerve-canals, which are difieult and delicate operations, requiring the touch of the hand on the tool to correctlylocate the position of the operating instrument in the root of the tooth and determine where and just how far it may be inserted and operated with safety. This tool enables me to treat the roots 0f the rear teeth conveniently withu out danger of breaking the operatingl instruu ment off in the root. The operating' insti-le ment is applied to the root of the tooth and manipulated by the rotator with the `fingers entirely outside of the mouth, thus avoiding obstruction to the view, as is the ease where the operating instrument is manipulated di rectly by the lingers.

lt will be seen that the various parts of my invention can be so formed and arranged as to produce a very simple and effective tool. The dentist can insert the tool into the mouth and operate it with one hand, While he holds the mouth-mirror in the other. The clamping-jaws of the tool hold firmly the smallest and inestinstrument that can possibly be used, while they permit of ready interchange of operating instruments, such as barbed or smoothed broaches, to ream nerves from the roots of the teeth and also drills or reamers to open the closed canals or enlarge or dress those from which the nerves have been removed. The delicate touch of the hand on the tool can be utilized to enable the dentist to know at all times the exact condition of the Work as it progresses.

Whilel have shown and described a peculiar construction, I do not Wish to be understood as limiting myself to it; but

l hat I claim, and desire to secure by Letters Patent, is-

In a dental handpiece, a tubular handle, a hollow head connected thereto, a rotary chuck-casing seated in said head and provided at its inner end with a gear, a chuck device in said casing and an operating-tool held by said chuck, a shaft mounted in said handle and having a gear adapted to mesh with the gear on said chuck-casing, a slotted sleeve mounted on said handle and a rotator rigidly mounted upon said shaft Within the slot of said sleeve, adapted to be turned by the thumb and finger of the same hand that holds the handpiece.

CHARLES P. GRAY. Vitnesses:

JAMES N. RAMSEY, O. J. FETTER. 

